Download Ch 4-1 Intro to Matrices

Example 1 Organize Data in a Matrix
Example 2 Dimensions of a Matrix
Example 3 Solve an Equation Involving Matrices
College Kaitlin wants to attend one of three Iowa
universities next year. She has gathered information
about tuition (T), room and board (R/B), and
enrollment (E) for the universities. Use a matrix to
organize the information. Which university’s total
cost is lowest?
Iowa State University:
T - $3132
R/B - $4432
E - 26,845
University of Iowa:
T - $3204
R/B - $4597
E - 28,311
University of Northern Iowa:
T - $3130
R/B - $4149
E - 14,106
Organize the data into labeled columns and rows.
T
R/B
E
ISU
UI
UNI
Answer: The University of Northern Iowa has the
lowest total cost.
Dining Out Justin is going out for lunch. The
information he has gathered from the two fast-food
restaurants is listed below. Use a matrix to organize
the information. When is each restaurant’s total cost
less expensive?
Burger Complex
Lunch Express
Hamburger Meal
$3.39 Hamburger Meal
$3.49
Cheeseburger Meal
$3.59 Cheeseburger Meal
$3.79
Chicken Sandwich Meal
$4.99 Chicken Sandwich Meal $4.89
Answer:
Hamburger
Meal
Cheeseburger
Meal
Chicken
Sandwich
Meal
Burger Complex
Lunch Express
The Burger Complex has the best price for hamburgers
and cheeseburgers. Lunch Express has the best price for
chicken sandwiches.
State the dimensions of matrix G if
2 rows
4 columns
Answer: Since matrix G has 2 rows and 4 columns, the
dimensions of matrix G are 2  4.
State the dimensions of matrix G if
Answer: 3  2
Solve
for x and y.
Since the matrices are equal, the corresponding
elements are equal. When you write the sentences to
solve this equation, two linear equations are formed.
This system can be solved using substitution.
Second equation
Substitute 3x – 2 for y.
Distributive Property
Add 4 to each side.
Divide each side by 7.
To find the value for y, substitute 1 for x in
either equation.
First equation
Substitute 1 for x.
Simplify.
Answer: The solution is (1, 1).
Solve
Answer: (2, 5)
for x and y.
Click the mouse button or press the
Space Bar to display the answers.